Method of rendering translucent sheets of paper, cardboard, and the like having drawings on it



l atenteci Aug. F7, 1923..

TP'ATENT orrren,

ALOIS ELEMENT, T5 HAMBURG, GERMANY.

MTHOD OF BENDERING TBANSLUCENT SHEETS 0E PAPER, CARDBOARD, AND THE LIKE HAVING DRAWINGS ON IT.

We Drawing.

To all whom it may concern:

Be it known that I, ALOIS KLEMENT, a citizen of Germany, residing at Hamburg, No. 14: Bethesdastrame, have invented new and useful Improvements in Methods of Rendering Translucent Sheets of Paper, Card-' board, and the like Having Drawings on It, of which the following is a specification. My present invention relates to drawings. and the like, and has for its object, to provide' a process for rendering pa er, tracing paper, card-board, and the li e, having drawings on it, translucent, for the purpose of allowing heliographic rints to be made therefrom. Drawings made on drawing board, such as bristol board, and the like, or on tracing paper, and other kinds of material or paper are not directly suited for the photo-printin process. To render such paper or car -board translucent, according to my invention the sheet is rubbed with a mixture consisting of castor oil and oil of turpentine. Hereby the pa er will be thoroughly soaked ith oil. A ter the oil. of turpentine has evaporated the paper will be translucent so that it will now be possible to make photo-prints therefrom.

In carrying out the invention the mixture of castor oil and oil of turpentine is applied with a sponge or a rag to the sheet of card-board or the like, and rubbed well into the same. Lines drawn with india ink will not be in'ured by the mixture and the rub bing in t ereof. This rubbing will, on the other-hand, remove dirt and pencil marks. Therefore drawings made with pencil v rendered invisible b be photo-printed. An

Application filed March 25, 192%). fierial No. 368,765.

should be rubbed on the reverse side, also printed plans and the like, because the lines on such drawings and plans would be washed awa or be paled bythe treatment.

On the thus treated drawing one may draw with ink, pencil, india ink, or the like, and evergline, even the finest will be clearly visible. rasures subsequently made may be a renewed treatment with the mixture. s the mixture will dry quickly, thus treated drawings may at once kind of drawing paper may be treated a ter the hereinbefore described process, and this treatment will not make'the paper wavy or brittle.

What I claim and desire to secure by Letters Patent of the United States, is:

1. A method of rendering translucent, sheets of paper, card-board, and the like, having drawings on it, consisting in treating the sheets with a mixture of castor oil 1 and oil of turpentine.

2. A method of rendering translucent, sheets of paper, card-board, and the like, having drawings on it, consisting in treating the sheets with a mixture of castor oil and oil of turpentine, and. allowing the oil of turpentine to evaporate.-

In testimony whereof I have signed my as name to this specification in the presence of two subscribing witnesses.

arms Knnrmrrr.

Witnesses: Fnmnmon JULIUS Po rnn, Annom Hnmnron Rononr Voss. 

